Pump



Aug. 22, 1967 r. STREULI 3,3363% PUMP Filed Sept. 27, 1965 2 SheetsSheet l T. STREULI Aug. 22, 1967 PUMP 2 Sheets-Sheet Filed Sept. 27, 1965 United States Patent 3,336,876 PUMP Theodor Streuli, Schaffhausen, Switzerland, assignor to Siemen & Hinsch m.b.H., Itzehoe, Holstein, Germany Filed Sept. 27, 1965, Ser. No. 490,469 Claims priority, application Germany, Oct. 7, 1964,

5 Claims. ci. 103-108) ABSTRACT OF THE DISCLOSURE This invention relates to a self-aspirating, multistage, reversible side channel rotary pump.

The inlet and outlet ports in the side channel of side channel rotary pumps are known to be often based on hydraulic principles in order to obtain a good delivery capacity, the utmost efliciency of the fluid supply, and particularly with self aspirating pumps, in order to obtain a suflicient delivery capacity of gas. If a side channel rotary pump is operated in the reverse direction of rotation so that the fluid flows in through the pressure slot in the side channel and leaves again by the suction port of the side channel respectively to the pump delivery chamber, the pump will deliver but, in comparison with normal rotational direction, its output is reduced. The reversal of the direction of rotation has an especially dis advantageous effect on the gas delivery capacity of the pump, so that in this case a self-aspirating pump can hardly be considered.

There are known constructions, which allow the pump to be operated in both rotational directions, and with which the output is similar in both directions, as are also the fluid and gas delivery capacities. In such constructions the suction and pressure flow ports of the side channel are very similar and also the wing profiles of the impeller wheels are symmetrically constructed. However, these pumps, as compared with normal side channel rotary pumps, possess a considerably reduced fluid and also gas delivery capacity, and therefore their application remains limited.

Moreover constructions are known in which direction of rotation is maintained constant while the direction of flow of the delivery agent is altered. The reversal takes place outside the pump through corresponding vents and adjustable valves. Such equipment however possesses the disadvantage of complicated assembly, hence they are expensive and are furthermore susceptible to wear.

In many (practical) industrial instances today, however, a simple pump is required, which can operate in both rotational directions and which possesses a suflicient gas delivery capacity in both rotational directions. The additional requirement often is that the output of the pump should be as large as possible and similar in both directions. It is therefore an object of the invention to provide a self-aspirating, multistage rotary pump, which whether rotated in clockwise or in anticlockwise direction will pump through at least one pump stage in normal delivery direction.

According to the invention at least one stage is developed for a delivery and rotational direction which is opposed to the normal delivery and rotational direction of the other stage or stages. Normal delivery direction means in this case, that the delivery agent in this stage enters by the suction port, practically corresponding to the favourably developed induction port in the side channel and leaves this again by the pressure port the external induction port in the control disc.

According to a feature of the invention, the pressure outlet ports of the side channels serving as outlets of the two external stages open out into the housing cover of the pump, thus in each direction of rotation the flow in the last pump stage is in the normal delivery direction.

It is thus ensured that the pump obtains the same value for the gas delivery capacity, as a normal side channel rotary pump, in clockwise rotation as well as anticlockwise similar to a multistage pump, which in gas delivery, delivers normally the last stage alone. If it is attempted to produce the same delivery capacity from the pump in both rotation directions, thus according to the invention it can be undertaken, with a pump of an even number of stages, to control the stages at any time the same amount of stages can be pumped through the pump in normal delivery direction both in clockwise and anticlockwise direction of rotation.

The invention also has the special advantage, that pumps, according to the invention, can be built from the ordinary parts of existing models of side channel pumps, if for each stage an additional balancer is provided for by a control disc. The invention therefore obviates the need for separate models for clockwise and anticlockwise rotational pumps, which were necessary with the known construction described earlier on.

The invention will now be described by way of example with reference to the accompanying drawings in which:

FIGURE 1 shows a longitudinal cross-section through a two-stage pump embodying the invention, and

FIGURE 2 shows an exploded view in perspective, of the side channel and control discs and impeller Wheels.

Elements associated with the two individual stages of the pump are designated by reference characters showing the indexes a and b, respectively.

Referring to FIGURES 1 and 2, a pump casing or housing 1a, 1b with connection portions 2a, 2b and passages 10a, 10b encloses side channel discs 3a, 3b in sealing relationship. The discs 3a, 3b comprise pressure slots in the form of outlet-type ports 6a, 6b. With normal delivery direction for the individual stage, the respective suction'type ports 8a, 8b serving as induction ports are situated in control discs 4a, 4b and open out into a common centre chamber 5. The discs 3a, 4a and 3b, 4b enclose respective chambers 11a, 11b wherein impellers 7a, 7b operate. As will be seen from the illustration and explained hereinafter, the last, in this case the second, pump stage is pumped through, in each rotational direction, in normal delivery direction. It is easily seen, that the pump delivers in both rotational directions, the same fluid and gas delivery capacity.

As will be seen from FIGURE 2, the discs 3a, 4a and the impeller 7a are identical with the discs 3b, 4b and impeller 71), respectively. Each set of parts, i.e., each stage, is constructed for optimum delivery in the normal direction of rotation of its impeller, the delivery of the respective stage being reduced during rotation in the opposite direction. As indicated in FIG. 2, the vane profiles of each propeller are asymmetrical, that is, the profile at one side of each vane is different from that at the other side. The parts 3a, 4a and 7a are arranged in the pump so that fluid will pass through this stage in the normal or optimum manner during rotation in the direction of the arrow A (anti-clockwise as seen in FIG. 2), that is,

fluid will then enter this stage through the suction-type port 8a and leave through the outlet-type port 6a as indicated by arrows at these ports in FIG. 2. On the other hand, the parts 312, 4b and 7b are arranged in the pump in a manner such that fluid would pass through this stage in the normal or optimum manner during rotation in the direction of the arrow B (clockwise as seen in FIG. 2), that is, fluid would then enter this stage through the suction-type port 8b and leave through the outlet-type port 6b as indicated by arrows at these ports in FIG. 2.

Both impellers are actuated by reversible driving means comprising a common shaft 9 (FIG. 1) and are selectively rotated together in clockwise or anti-clockwise direction. If, for example, the impellers 7a, 7b are rotated in the direction of the arrow A in FIG. 2, fluid will enter the pump through passage 10b (FIG. 1) and outlet-type port 6b (FIG. 2) and under the action of impeller 7b will pass through suction-type port 8b, central chamber 5, and suction-type port 8a, whereupon due to the action of impeller 7a the fluid will be expelled through outlettype port 6a and passage 10a. If the direction of rotation is reversed, fluid will flow in the opposite direction, that is, fluid will enter the pump through passage 10a and leave through passage 10b. In either direction of rotation, therefore, one stage of the two-stage pump shown is traversed by fluid in the normal or optimum direction while at the same time the other stage is traversed in its abnormal direction.

I claim:

1. In a reversible rotary, self-priming side channel pump for delivery of fluid, at least one side channel stage constructed and arranged for optimum operation in predetermined directions of rotation and fluid flow, at least one other side channel stage constructed and arranged for optimum operation in opposite directions of rotation and fluid flow, said stages being connected for operation in series, and reversible drive means for selectively actuating both stages together for operation in said predetermined directions of rotation and fluid flow at one time and for operation in the opposite directions of rotation and fluid flow at another time.

2. The combination as specified in claim 1, wherein said pump includes housing means having passages therein, and wherein said stages are the first stage and the last stage of said pump, respectively, and each of said first and last stages has an outlet-type port communicating with one of said passages.

3. In a reversible rotary, self-priming side channel pump for delivery of fluid, a predetermined number of side channel stages constructed and arranged for optimum delivery during clockwise rotation but reduced delivery during anti-clockwise rotation, an equal number of other side channel stages constructed and arranged for reduced delivery during clockwise rotation but optimum delivery during anti-clockwise rotation, and reversible drive means for selectively operating said stages and said other stages together in clockwise direction at one time and in anticlockwise direction at another time, said stages and said other stages being connected to each other for operation in series in a manner such that the direction of fluid flow will be reversed upon reversal of the rotational direction and the number of stages traversed by fluid under optimum conditions will be the same in both directions of rotation.

4. A reversible rotary, self-priming side channel pump for delivery of fluid, comprising first casing means having a first passage therein, a first side channel disc connected to said first casing means and having a first outlet-type port therethrough communicating with said first passage, a first control disc forming a first chamber with said first side channel disc and having a first suction-type port therethrough, a first impeller positioned in said first chamber, said first impeller having asymmetrical vanes arranged for optimum operation in a predetermined direction of rotation, at least one additional control disc connected to said first control disc and having an additional suction-type port therethrough arranged for communication with said first suction-type port, at least one additional side channel disc forming a second chamber with said additional control disc and having an additional outlet-type port therethrough, a second impeller positioned in said second chamber, said second impeller having asymmetrical vanes arranged for optimum operation in the other direction of rotation, second casing means connected to said additional side channel disc and having a second passage therein communicating with said additional outlet-type port, and reversible drive means for selectively operating both impellers together in either direction of rotation in a manner such that during rotation in said predetermined direction said fluid will enter through said second passage and additional outlet-type port and pass through said second chamber, additional suction-type port, first suction-type port, first chamber, and first outlet-type port to be expelled through said first passage, and vice versa.

5. A pump as specified in claim 4, wherein said first and additional control discs have a central chamber therebetween, said first and additional suction-type ports communicating with said central chamber.

References Cited UNITED STATES PATENTS 2,916,997 12/1959 Terrie 103-2 3,135,215 6/1964 Smith 103--108 FOREIGN PATENTS 902,298 1/1954 Germany.

DONLEY J. STOCKING, Primary Examiner.

HENRY F. RADUAZO, Examiner. 

1. IN A REVERSIBLE ROTARY, SELF-PRIMING SIDE CHANNEL PUMP FOR DELIVERY OF FLUID, AT LEAST ONE SIDE CHANNEL STAGE CONSTRUCTED AND ARRANGED FOR OPTIMUM OPERATION IN PREDETERMINED DIRECTIONS OF ROTATION AND FLUID FLOW, AT LEAST ONE OTHER SIDE CHANNEL STAGE CONSTRUCTED AND ARRANGED FOR OPTIMUM OPERATION IN OPPOSITE DIRECTIONS OF ROTATION AND FLUID FLOW, SAID STAGES BEING CONNECTED FOR OPERATION IN SERIES, AND REVERSIBLE DRIVE MEANS FOR SELECTIVELY ACTUATING BOTH STAGES TOGETHER FOR OPERATION IN SAID PREDETERMINED DIRECTIONS OF ROTATION AND FLUID FLOW AT ONE TIME AND FOR OPERATION IN THE OPPOSITE DIRECTIONS OF ROTATION AND FLUID FLOW AT ANOTHER TIME. 